#ifndef __ENCRYPT_SM4_C
#define __ENCRYPT_SM4_C

#include "encryptionSM4.h"

/****************************** 系统参数FK的取值 ****************************************/
// FK = 32位4字节 * 4 = 128位 = 16字节 = 4项
const u32 TBL_SYS_PARAMS[4] = { 
		0xa3b1bac6,0x56aa3350,0x677d9197,0xb27022dc
};
/******************************定义固定参数CK的取值****************************************/
// 密码扩展运算用：CK参数 = 8*128位 = 1024位 = 32个32位 = 32个4字节 = 32项
// 因此能通过此，算出32位的轮密钥。
const u32 TBL_FIX_PARAMS[32] = {
		0x00070e15,0x1c232a31,0x383f464d,0x545b6269,
		0x70777e85,0x8c939aa1,0xa8afb6bd,0xc4cbd2d9,
		0xe0e7eef5,0xfc030a11,0x181f262d,0x343b4249,
		0x50575e65,0x6c737a81,0x888f969d,0xa4abb2b9,
		0xc0c7ced5,0xdce3eaf1,0xf8ff060d,0x141b2229,
		0x30373e45,0x4c535a61,0x686f767d,0x848b9299,
		0xa0a7aeb5,0xbcc3cad1,0xd8dfe6ed,0xf4fb0209,
		0x10171e25,0x2c333a41,0x484f565d,0x646b7279
};

/****************************** SBox参数列表 **************************************/
// S盒：256字节;
const u8 TBL_SBOX[256] = { 
		0xd6,0x90,0xe9,0xfe,0xcc,0xe1,0x3d,0xb7,0x16,0xb6,0x14,0xc2,0x28,0xfb,0x2c,0x05,
		0x2b,0x67,0x9a,0x76,0x2a,0xbe,0x04,0xc3,0xaa,0x44,0x13,0x26,0x49,0x86,0x06,0x99,
		0x9c,0x42,0x50,0xf4,0x91,0xef,0x98,0x7a,0x33,0x54,0x0b,0x43,0xed,0xcf,0xac,0x62,
		0xe4,0xb3,0x1c,0xa9,0xc9,0x08,0xe8,0x95,0x80,0xdf,0x94,0xfa,0x75,0x8f,0x3f,0xa6,
		0x47,0x07,0xa7,0xfc,0xf3,0x73,0x17,0xba,0x83,0x59,0x3c,0x19,0xe6,0x85,0x4f,0xa8,
		0x68,0x6b,0x81,0xb2,0x71,0x64,0xda,0x8b,0xf8,0xeb,0x0f,0x4b,0x70,0x56,0x9d,0x35,
		0x1e,0x24,0x0e,0x5e,0x63,0x58,0xd1,0xa2,0x25,0x22,0x7c,0x3b,0x01,0x21,0x78,0x87,
		0xd4,0x00,0x46,0x57,0x9f,0xd3,0x27,0x52,0x4c,0x36,0x02,0xe7,0xa0,0xc4,0xc8,0x9e,
		0xea,0xbf,0x8a,0xd2,0x40,0xc7,0x38,0xb5,0xa3,0xf7,0xf2,0xce,0xf9,0x61,0x15,0xa1,
		0xe0,0xae,0x5d,0xa4,0x9b,0x34,0x1a,0x55,0xad,0x93,0x32,0x30,0xf5,0x8c,0xb1,0xe3,
		0x1d,0xf6,0xe2,0x2e,0x82,0x66,0xca,0x60,0xc0,0x29,0x23,0xab,0x0d,0x53,0x4e,0x6f,
		0xd5,0xdb,0x37,0x45,0xde,0xfd,0x8e,0x2f,0x03,0xff,0x6a,0x72,0x6d,0x6c,0x5b,0x51,
		0x8d,0x1b,0xaf,0x92,0xbb,0xdd,0xbc,0x7f,0x11,0xd9,0x5c,0x41,0x1f,0x10,0x5a,0xd8,
		0x0a,0xc1,0x31,0x88,0xa5,0xcd,0x7b,0xbd,0x2d,0x74,0xd0,0x12,0xb8,0xe5,0xb4,0xb0,
		0x89,0x69,0x97,0x4a,0x0c,0x96,0x77,0x7e,0x65,0xb9,0xf1,0x09,0xc5,0x6e,0xc6,0x84,
		0x18,0xf0,0x7d,0xec,0x3a,0xdc,0x4d,0x20,0x79,0xee,0x5f,0x3e,0xd7,0xcb,0x39,0x48
};


//使用 SM4 加密数据时，被加密数据的长度必须是16的倍数，不是倍数的要补足。
//详见 SM4 相关函数

//4字节无符号数组转无符号long型
void uChar4Arr2uLong(u8 *in, u32 *out){
		int i = 0;
		*out = 0;
		for (i = 0; i < 4; i++) *out = ((u32)in[i] << (24 - i * 8)) ^ *out;
}

//无符号long型转4字节无符号数组
void uLong2uChar4Arr(u32 in, u8 *out){ 
		int i = 0;
		//从32位unsigned long的高位开始取
		for (i = 0; i < 4; i++)	*(out + i) = (u32)(in >> (24 - i * 8));
}

//左移，保留丢弃位放置尾部
u32 move(u32 data, int length){ 
		u32 result = 0;
		result = (data << length) ^ (data >> (32 - length));
		return result;
}

//秘钥处理函数,先使用Sbox进行非线性变化，再将线性变换L置换为L'
u32 func_key(u32 input){ 
		int i = 0;
		u32 ulTmp = 0;
		u8 ucIndexList[4] = { 0 };
		u8 ucSboxValueList[4] = {  0 };
		uLong2uChar4Arr(input, ucIndexList);
		for (i = 0; i < 4; i++){ 
				ucSboxValueList[i] = TBL_SBOX[ucIndexList[i]];
		}
		uChar4Arr2uLong(ucSboxValueList, &ulTmp);
		ulTmp = ulTmp ^ move(ulTmp, 13) ^ move(ulTmp, 23);
		return ulTmp;
}

//加解密数据处理函数,先使用Sbox进行非线性变化，再进行线性变换L
u32 func_data(u32 input){
		int i = 0;
		u32 ulTmp = 0;
		u8 ucIndexList[4] = {  0 };
		u8 ucSboxValueList[4] = {  0 };
		uLong2uChar4Arr(input, ucIndexList);
		for (i = 0; i < 4; i++){
				ucSboxValueList[i] = TBL_SBOX[ucIndexList[i]];
		}
		uChar4Arr2uLong(ucSboxValueList, &ulTmp);
		ulTmp = ulTmp ^ move(ulTmp, 2) ^ move(ulTmp, 10) ^ move(ulTmp, 18) ^ move(ulTmp, 24);
		return ulTmp;
}

//加密函数（可以加密任意长度数据，16字节为一次循环，不足部分补0凑齐16字节的整数倍）
//len:数据长度(任意长度数据) key:密钥（16字节） input:输入的原始数据 output:加密后输出数据
void encode_SM4(u8 len,u8 *key, u8 *input, u8 *output){ 
		int i = 0,j=0; 
	  u32 ulKeyTmpList[4] = {  0 };   //存储密钥的u32数据
		u32 ulKeyList[36] = {  0 };     //用于密钥扩展算法与系统参数FK运算后的结果存储
		u32 ulDataList[36] = {  0 };    //用于存放加密数据
		u8 *p = (u8 *)malloc(50);       //定义一个50字节缓存区
		
		/***************************开始生成子秘钥********************************************/
		uChar4Arr2uLong(key, &(ulKeyTmpList[0]));
		uChar4Arr2uLong(key + 4, &(ulKeyTmpList[1]));
		uChar4Arr2uLong(key + 8, &(ulKeyTmpList[2]));
		uChar4Arr2uLong(key + 12, &(ulKeyTmpList[3]));
		ulKeyList[0] = ulKeyTmpList[0] ^ TBL_SYS_PARAMS[0];
		ulKeyList[1] = ulKeyTmpList[1] ^ TBL_SYS_PARAMS[1];
		ulKeyList[2] = ulKeyTmpList[2] ^ TBL_SYS_PARAMS[2];
		ulKeyList[3] = ulKeyTmpList[3] ^ TBL_SYS_PARAMS[3];
		//32次循环迭代运算
		for (i = 0; i < 32; i++){ 
				//5-36为32个子秘钥
				ulKeyList[i + 4] = ulKeyList[i] ^ func_key(ulKeyList[i + 1] ^ ulKeyList[i + 2] ^ ulKeyList[i + 3] ^ TBL_FIX_PARAMS[i]);
		}
		/***********************************生成32轮32位长子秘钥结束**********************************/
		for (i = 0; i < len; i++)  *(p + i) = *(input + i);        //将输入数据存放在p缓存区
		for (i = 0; i < 16-len % 16; i++)  *(p + len + i) = 0;     //将不足16位补0凑齐16的整数倍
		//进行循环加密,并将加密后数据保存（可以看出此处是以16字节为一次加密，进行循环，即若16字节则进行一次，17字节补0至32字节后进行加密两次，以此类推）		
		for (j = 0; j < len / 16 + ((len % 16) ? 1:0); j++) { 
				//开始处理加密数据
				uChar4Arr2uLong(p + 16 * j, &(ulDataList[0]));
				uChar4Arr2uLong(p + 16 * j + 4, &(ulDataList[1]));
				uChar4Arr2uLong(p + 16 * j + 8, &(ulDataList[2]));
				uChar4Arr2uLong(p + 16 * j + 12, &(ulDataList[3]));
				//加密
				for (i = 0; i < 32; i++){
						ulDataList[i + 4] = ulDataList[i] ^ func_data(ulDataList[i + 1] ^ ulDataList[i + 2] ^ ulDataList[i + 3] ^ ulKeyList[i + 4]);
				}
				//将加密后数据输出 
				uLong2uChar4Arr(ulDataList[35], output + 16 * j);
				uLong2uChar4Arr(ulDataList[34], output + 16 * j + 4);
				uLong2uChar4Arr(ulDataList[33], output + 16 * j + 8);
				uLong2uChar4Arr(ulDataList[32], output + 16 * j + 12);
		}
		free(p);
}

//解密函数（与加密函数基本一致，只是秘钥使用的顺序不同，即把钥匙反着用就是解密）
//len:数据长度 key:密钥 input:输入的加密后数据 output:输出的解密后数据
void decode_SM4(u8 len,u8 *key, u8 *input, u8 *output){ 
		int i = 0,j=0;
		u32 ulKeyTmpList[4] = { 0 };  //存储密钥的u32数据
		u32 ulKeyList[36] = { 0 };    //用于密钥扩展算法与系统参数FK运算后的结果存储
		u32 ulDataList[36] = { 0 };   //用于存放加密数据
		// 开始生成子秘钥 
		uChar4Arr2uLong(key, &(ulKeyTmpList[0]));
		uChar4Arr2uLong(key + 4, &(ulKeyTmpList[1]));
		uChar4Arr2uLong(key + 8, &(ulKeyTmpList[2]));
		uChar4Arr2uLong(key + 12, &(ulKeyTmpList[3]));
		ulKeyList[0] = ulKeyTmpList[0] ^ TBL_SYS_PARAMS[0];
		ulKeyList[1] = ulKeyTmpList[1] ^ TBL_SYS_PARAMS[1];
		ulKeyList[2] = ulKeyTmpList[2] ^ TBL_SYS_PARAMS[2];
		ulKeyList[3] = ulKeyTmpList[3] ^ TBL_SYS_PARAMS[3];
		//32次循环迭代运算
		for (i = 0; i < 32; i++){
				//5-36为32个子秘钥
				ulKeyList[i + 4] = ulKeyList[i] ^ func_key(ulKeyList[i + 1] ^ ulKeyList[i + 2] ^ ulKeyList[i + 3] ^ TBL_FIX_PARAMS[i]);
		}
		//生成32轮32位长子秘钥结束 
		//进行循环加密,并将加密后数据保存
		for (j = 0; j < len / 16; j++){ 
				//开始处理解密数据
				uChar4Arr2uLong(input + 16 * j, &(ulDataList[0]));
				uChar4Arr2uLong(input + 16 * j + 4, &(ulDataList[1]));
				uChar4Arr2uLong(input + 16 * j + 8, &(ulDataList[2]));
				uChar4Arr2uLong(input + 16 * j + 12, &(ulDataList[3]));
				//解密
				for (i = 0; i < 32; i++){
						ulDataList[i + 4] = ulDataList[i] ^ func_data(ulDataList[i + 1] ^ ulDataList[i + 2] ^ ulDataList[i + 3] ^ ulKeyList[35 - i]);//与加密唯一不同的就是轮密钥的使用顺序
				}
				//将解密后数据输出
				uLong2uChar4Arr(ulDataList[35], output + 16 * j);
				uLong2uChar4Arr(ulDataList[34], output + 16 * j + 4);
				uLong2uChar4Arr(ulDataList[33], output + 16 * j + 8);
				uLong2uChar4Arr(ulDataList[32], output + 16 * j + 12);
		}
}

//无符号字符数组转16进制打印
void print_hex(u8 *data, int len){
		int i = 0;
		char alTmp[16] = {'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f' };
		for (i = 0; i < len; i++){ 
				printf("%c", alTmp[data[i] / 16]);
				printf("%c", alTmp[data[i] % 16]);
		    putchar(' ');
		}
		putchar('\n');
}


///*在主函数中实现任意字节加密与解密，并且结果正确*/
//int main(void){ 
//		u8 i,len;
//		u8 encode_Result[50] = {  0 };    //定义加密输出缓存区
//		u8 decode_Result[50] = {  0 };    //定义解密输出缓存区

//		//定义16字节的密钥
//		u8 key[16] = {0x01,0x23,0x45,0x67,0x89,0xab,0xcd,0xef,0xfe,0xdc,0xba,0x98,0x76,0x54,0x32,0x10 };       
//		//u8 Data_plain[18] = { 0x01,0x23,0x45,0x67,0x89,0xab,0xcd,0xef,0xfe,0xdc,0xba,0x98,0x76,0x54,0x32,0x10,0x01,0x23 };//定义18字节的原始输入数据（测试用）
//		//u8 Data_plain[32] = { 0x01,0x23,0x45,0x67,0x89,0xab,0xcd,0xef,0xfe,0xdc,0xba,0x98,0x76,0x54,0x32,0x10,0x01,0x23,0x45,0x67,0x89,0xab,0xcd,0xef,0xfe,0xdc,0xba,0x98,0x76,0x54,0x32,0x10 };//定义32字节的原始输入数据（测试用）
//		u8 Data_plain[16] = {0x01,0x23,0,0,0,0,0,0,0,0,0,0,0,0,0,0};//定义16字节的原始输入数据（测试用）

//		//得到扩充后的字节数（解密函数会用到）
//		len = 16 * (sizeof(Data_plain) / 16) + 16 * ((sizeof(Data_plain) % 16) ? 1 : 0);
//		encode_fun(sizeof(Data_plain),key, Data_plain, encode_Result);  //数据加密
//		printf("加密后数据是：\n");
//		for (i = 0; i < len ; i++)
//		printf("%x ", *(encode_Result + i));
//		/*注意：此处解密函数的输入数据长度应为扩展后的数据长度，即必为16的倍数*/		
//		decode_fun(len,key, encode_Result, decode_Result);      //数据解密
//		printf("解密后数据是：\n");
//		for (i = 0; i < len; i++)
//		printf("%x ", *(decode_Result + i));
//		system("pause");
//		return 0;
//}

#endif

